Bargain Tefillin: Six questions you should ask before you buy
One should definitely be wary of very inexpensive tefillin. Even if you want to really on many leniencies, it's hard to make tefillin that meet minimal halachic requirements without compromising on the basics. Here's a question we received from a prospective tefillin peshutim buyer.
Shalom, I am looking for a Tefillin for my Bar Mitzvah...